Thermal energy generated by the electrical resistance of a 5-mm-diameter and 4-m- long bare cable is dissipated to the surrounding air at 80°C. The voltage drop and the electric current across the cable in steady operation are measured to be 18 V and 5 A, respectively. Disregarding radiation, estimate the surface temperature of the cable. Evaluate air properties at a film temperature of 100°C and 1 atm pressure.

Thermal energy generated by the electrical resistance of a 5-mm-diameter and 4-m- long bare cable is dissipated to the surrounding air at 80°C. The voltage drop and the electric current across the cable in steady operation are measured to be 18 V and 5 A, respectively. Disregarding radiation, estimate the surface temperature of the cable. Evaluate air properties at a film temperature of 100°C and 1 atm pressure.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter6: Forced Convection Over Exterior Surfaces

Section: Chapter Questions

Problem 6.29P

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